1. Field of the Invention
The present invention relates to medical devices, and more particularly to a drainage tube system and components thereof for draining body fluids from body cavities.
2. General Background and Prior Art
During surgical procedures and following completion of surgery, drainage tubes are employed to suction body fluids from the surgical field or from within the closed wound. Following a thoracotomy, for example, drainage tubes having one or more lumens extending between the proximal and distal ends thereof are positioned with the distal end located within the chest and the body of the tube passing through the closed incision or a separate, small incision so that fluids accumulating normally postoperatively in the chest, for example, drain and flow by gravity and internal pressure to a suitable collection vessel. Suction may be applied to the drainage lumen at the proximal end of the tube to encourage the flow of body fluid. The removal of such fluids, including blood, pus, cells, blood clots, other fluids and tissue fragments ("body fluids") following surgery is beneficial to relieve pressure and avoid and/or control infections. Generally such drainage systems are referred to as "wound" drainage systems, whether or not surgery was precipitated by trauma.
To this end, a number of wound drainage systems of the type which include catheter or tube members which can be so installed such that they extend to the collection vessel have been heretofore made available. Systems of this general type have included simple, single lumen, tubes employing gravity, internal pressure or suction as described above, double lumen tubes and triple lumen tubes. The second lumen of double lumen tubes may be employed to introduce irrigating fluids into the body cavity being drained to dilute and encourage the flow of body fluids or may be used with an appropriate anti-bacterial filter at the proximal end of the second lumen to ventilate the body cavity to also encourage the flow of body fluids through the first lumen.
Triple lumen drainage tubes or catheters of the type disclosed in U.S. Pat. No. 4,508,533 to Abramson and described in the article by D. J. Abramson, "Improved Triple Lumen All Purpose Drains and their Care and Management", in THE AMERICAN SURGEON, vol. 49, no. 10, pp. 539-541, (October, 1983), both incorporated herein by reference, provide separate irrigation and ventilation lumens with an appropriate, removable, three lumen adaptor having appropriate valves, caps and anti-bacterial filter. During periods when the irrigation lumen is not used for irrigating the cavity, it is blocked off or otherwise closed to prevent unfiltered air, which may contain bacteria, from entering the body cavity through it.
The surgical insertion of such drainage tubes or catheters is usually made before the incision is closed through a stab wound made at a distance from the surgical incision so that the healing of the usually larger incision may proceed without complications arising from mechanical movement of the tube and possible contamination of the incision. A subcutaneous tunnel is created to the cavity to be drained, and the tube is introduced through the incision so that its proximal end is advanced through the tunnel and emerges from the stab wound. The distal end is placed in the cavity to be drained, following the precautions on placement described in the above-incorporated Abramson article. Drainage tubes or catheters with integrally formed, multi-branch connectors for drainage, irrigation, and/or ventilation are inconvenient or impossible to pull through a subcutaneous tunnel and reasonably sized stab wound. Introducing the tube or catheter distal end first requires tunneling a forceps to the stab wound and is not favored.
Depending on the nature of the procedure, surgeons find that in certain situations the simple single lumen drainage tube is sufficient. In other procedures, it may be desirable to employ the double or triple lumen tube coupled to appropriate irrigation or ventilation systems. A need exists for an adaptable multi-lumen drainage tube that may be employed in applications calling for a single lumen or two or more lumens and that may be easily introduced surgically in the manner described above and coupled securely with suitable adaptors at its proximal end.
While devices of the above-described type have frequently been used for draining, ventilating and irrigating wounds, they have not always been entirely effective for several reasons. The body fluid leaving the body cavity through the drainage lumen contains a large percentage of blood which can form clots in the lumen or at the distal end thereof resulting in stoppage. Consequently, medical personnel attending the patient must frequently check the patency of the lumen so that the drainage system remains operating effectively.
The application of suction to the drainage lumen to encourage drainage is not always effective even when irrigation and/or ventilation of the body cavity is provided. Relatively low suction pressure is necessary to avoid creating or exacerbating a negative pressure within the body cavity which, in the case of the thoracic cavity could effect lung pressure. Conversely, a positive flow of air or irrigation fluid into the lung cavity to encourage drainage could introduce a positive pressure that could lead to deflation or collapse of the lungs. In other applications, high positive and negative pressure may adversely influence body organs or cause discomfort to the patient.
Current techniques for cleaning out areas within the drainage tube containing occluding body tissue and blood clots include periodically increasing the applied suction pressure or the applied irrigation pressure. In addition, it has been proposed in a system employing a medical underwater seal collection vessel to provide a venting valve coupled to the venting lumen and periodically closing the valve to increase negative pressure inside the cavity and to suddenly open the valve so that the incoming air effectively increases the pressure and hopefully dislodges the occluding matter as disclosed in U.S. Pat. No. 4,735,606 to Davison. In the U.S. Pat. No. '606 patent, it is also proposed to manually strip the drain tube by hand squeezing the tube lumen in order to obtain momentary high negative pressures in the distal portion of the lumen in the cavity.
In coaxial, double lumen sump catheters, a further manual cleaning technique for cleaning obstructions from the inner suction lumen has been proposed in the article by J. P. A. M. Vroemen, "A Simple Procedure for Relieving Obstruction of Sump Catheters", cite needed. This technique involves slitting the outer lumen proximal to the percutaneous entry and manually snagging the inner lumen and retracting it proximally to pull it through the slit. The exposed distal length of the inner lumen is manually cleaned and reintroduced through the slit and advanced distally. The slit is then taped closed. This technique poses the risk of contamination and weakens the catheter. It cannot be used in side-by-side lumen catheters, e.g. the Abramson triple lumen catheter described above.
In spite of these improvements, a need remains for an effective and easily manipulative apparatus for removing clots and body tissue from drainage lumens in such drainage catheter systems.